时间:2019-01-30 作者:英语课 分类:农业与发展


英语课

AGRICULTURE REPORT - Cover Crops
By Mario Ritter


Broadcast: Tuesday, March 23, 2004


This is Steve Ember with the VOA Special English Agriculture Report.


The idea to grow a crop that improves the land and prepares it for other crops is thousands of years old. But scientists continue to search for new and better ways to use what are called cover crops.


Aref Abdul-Baki is with the Agricultural Research Service of the United States Department of Agriculture. He works at the Sustainable Agricultural Systems Laboratory in Beltsville, Maryland.


Mister Abdul-Baki has found some cover crops that resist worms that attack tomatoes. These crops are sunn hemp 1, cowpea and velvet 2 bean. They are planted during the months when the main crops are not normally grown. In states with moderate climates like Maryland and Virginia, the winter months are a good time to grow cover crops.


For tomatoes, cover crops can be planted in September. They can be turned over in the soil in May. The same method can be used for other summer crops like peppers, sweet corn, green beans and some melons.


After the cover crop is cut and turned, the result is a layer of organic material. This will provide fertilizer for the new crop. Also, the cover crop provides extra nitrogen to the soil.


Cover crops mixed with soil into mulch prevents the growth of unwanted plants. It also keeps soil from drying out and prevents the loss of soil.


In hot, dry parts of California, cover crops help keep down soil temperatures. They also reduce water loss and erosion.


Mister Abdul-Baki has shown that cover crops can save farmers a lot of money. Tomato farmers, for example, have used methyl bromide to treat their soil before they plant their tomatoes. This chemical kills many kinds of organisms that harm crops. Such treatment can increase the size of the harvest. But the government restricts the use of methyl bromide. And countries have agreed to an international treaty to ban it.


Mister Abdul-Baki has found that farmers who use cover crops with tomatoes save one-thousand-four hundred dollars per hectare. Farmers save on chemicals and also fertilizer. And Mister Abdul-Baki says the farmer produce as many, or more, tomatoes per hectare as compared to no use of cover crops.


Some cover crops provide enough seed for the next growing season. This can reduce costs even more.


This VOA Special English Agriculture Report was written by Mario Ritter. This is Steve Ember.



n.大麻;纤维
  • The early Chinese built suspension bridges of hemp rope.古代的中国人建造过麻绳悬索桥。
  • The blanket was woven from hemp and embroidered with wool.毯子是由亚麻编织,羊毛镶边的。
n.丝绒,天鹅绒;adj.丝绒制的,柔软的
  • This material feels like velvet.这料子摸起来像丝绒。
  • The new settlers wore the finest silk and velvet clothing.新来的移民穿着最华丽的丝绸和天鹅绒衣服。
学英语单词
abnormality of parturient canal
activated-sludge process
adhesiones
Amphipora
application slave
arboriculturists
arnab
arthritislike
assay foot
back-formation, back formation
balloon cyst
battens down
belonged to
bifurcation (of trachea)
capital growth bond
Carlylese
cicatrizing enteritis
compact radio source
constant composition index
cookiis
corroboration
Dabki
dezionizes
die with one's shoes
dreamina
dvi-manganese
dwight daviss
E.&O.E.
elastic container
esea
ethocaine
Etjo
fricatively
geosacred
giono
gluten-free diets
gold match
henry watson fowlers
high sign
hummin'
hyperbolic invariant set
insulated terminal
jade vine
janece
judge panel
leg-up
lidner
loti
magnetic tape check
mandibular prominence
mealte
median aperture of fourth ventricle
mess ... around
Mihǎileni
mining in severe cold district
MPS
muspratt
non-linear reflection
nostoc paludosum
oil-control
oleomargarin
one's own worst enemy
operations schedule
over-size goods
own her
panty check
preeclemptic toxemia
princ.
process photography
Recke
relief worker
resultant law
Rickettsia fletcheri
rigid-axle type suspension
RNA-OUT
salt gauge
semen assessment
shepperton
shooman
short period seismometer
Siberian fritillary bulb
signal-like density distribution
smack calf's skin
snap riveting
St-Martin-d'Auxigny
statement of financial income
steam iron generator
system supplied subroutine
take on something
Tambor, R.
thinnesses
three-lobe oil pump
timbreless
tow-away zone
trash plow
uninsulation
uxorious
weewees
weigh box
wild horses wouldn't drag me
Wilson willow
x (reactance)